Best Attic Fan (2021 Review)

Looking for the best attic fan for your home?

Look no further!

In this proHVACinfo guide, you’ll learn:

  • What are attic fans? (why are they so important?
  • What are the different types of attic fans? (learn which is right for you)
  • How do attic fans work? (cooling without air conditioning)
  • What do you look for in the best box fans? (don’t forget these things!)

And much more!

proHVACinfo | Attic Fans

In a hurry? Check out our quick roundup of the best attic fans!

ImageProduct
digital-business-prep-table__image
QuietCool Smart Attic Gable Fan
  • Energy Efficient Motor
  • App Control
  • Safety Shutdown
  • Energy Efficient Motor
  • App Control
  • Safety Shutdown
View on Amazon
digital-business-prep-table__image
Remington Solar Attic Fan
  • Brushless Motor
  • Hail & Weather Resistant
  • Solar Powered
  • Brushless Motor
  • Hail & Weather Resistant
  • Solar Powered
View on Amazon
digital-business-prep-table__image
iPower 12 Inch Shutter Fan
  • Corrosion Resistant Aluminum Construction
  • Easy Installation
  • Auto Gravity Shutters
  • Corrosion Resistant Aluminum Construction
  • Easy Installation
  • Auto Gravity Shutters
View on Amazon
digital-business-prep-table__image
Cool Attic Gable Mount Ventilator
  • Includes Adjustable Thermostat
  • Galvanized Steel
  • Precision Balanced
  • Includes Adjustable Thermostat
  • Galvanized Steel
  • Precision Balanced
View on Amazon
digital-business-prep-table__image
AC Infinity Airlift T10 Shutter Fan
  • Programmable Controller
  • IP44 Rated
  • High Flow Fan
  • Programmable Controller
  • IP44 Rated
  • High Flow Fan
View on Amazon

What Are Attic Fans?

Attic fans are specialist fans that are typically mounted in a gable end of an attic or in some cases directly in your roof.

The purpose of an attic fan is to take the hot, moist air commonly found in attics and move it to the exterior of the home.

Why is this useful?

Think about the sun beating down on your home during a hot summer day.

Your home’s roof is what’s directly exposed to the sun, so the heat is first transferred to the attic, where it then radiates throughout the rest of the home.

Think of your attic as the first line of defense when it comes to keeping your home cool.

Without appropriate ventilation, the temperature of an attic can reach well over 100 degrees.

If you’re able to increase ventilation and lower the temperature in your attic, the rest of the home will benefit as a result (because it isn’t getting as much heat from the attic).

This not only keeps you cooler, it also lightens the load on your air conditioning system, improving its effectiveness, longevity, and decreasing your utility bills in the process.

The high temperatures in your attic can also be a source of significant moisture buildup, which can degrade the integrity of your roof over time.

What’s more, if your home has any ductwork or HVAC equipment, the lower temperature brought about by an attic fan can prevent those fixtures from overheating!

What Are The Different Types Of Attic Fans?

Attic fans are usually broken into 2 categories, with some further subcategories based upon which you choose. Let’s learn more!

Roof Mounted

Roof mounted fans, as you’d expect, need you to install a ventilation port close to the peak of your roof.

The fan is mounted on a plate which sits over this ventilation port. Roof mounted fans are usually easiest to install.

Roof mounted fans, due to their horizontal installation, can actually be equipped with solar panels, making them effectively free to run.

They don’t require any mains electricity, which means no wiring, and no extension cords. Alternatively, they can be electrically powered.

The motors aren’t huge, so they won’t draw too much power, and electricity costs shouldn’t be a concern.

Gable End

These fans are mounted vertically in your home’s gable end, and typically have vents, or louvers to prevent birds, squirrels etc. from entering and setting up camp in your attic.

So, which is best?

It all depends on what you’re looking for.

Roof mounted fans, as we mentioned, are typically easiest to install, and offer incredible efficiency thanks to the solar power options.

Having said that, because the fans on gable end mounted models are usually larger, they have a noticeably better cooling capacity.

How do Attic Fans Work?

Attic fans work on a simple principle, hot air out, fresh air in.

As the attic fan expels hot, humid air from your attic, fresh air from outside is drawn into the space through the soffit vents.

This keeps a constant cycle of fresh air moving through the attic whenever the fan is running.

These fans usually operate via a thermostat that automatically turns the fan on and off depending on the temperature set.

You should have the option to control the kick in/shut down temperature.

By keeping the attic cool, you will also assist in keeping the rest of your home cool, so a small investment in an attic fan has the potential to save you money every month in energy bills.

In addition to lowering energy costs, keeping the air cool and dry will help to prevent mold, which can also extend the life of your roof.

Replacement roofs are expensive, so squeezing every possible day out of the one you have is important, and a good attic fan can help.

What Do You Look For In The Best Attic Fans?

Attic fans probably deal with more punishment than you could ever possibly throw at a fan you’d use inside your home, or even in your garage.

The intense heat takes its toll on even the strongest components, so in order to get the best possibly performance and longest life out of your attic fan, look for these features.

Metal Construction

Ensure that you choose an attic fan that features all metal construction.

Plastic components will be easily damaged by UV, leaving them brittle, and with the constant vibration and torque forced placed upon these parts, they can easily suffer catastrophic failure.

Thermostat Control

Some cheaper attic fans only feature an on/off switch, meaning you either have to go up into the attic to turn the fan on or off (when you actually remember), or you need to wire a switch down into the living space in your home.

Neither are ideal scenarios. Instead, look for a fan that features a controllable thermostat that can be programmed to turn the fan on or off when certain temperature thresholds are met.

Humidistat

Attic fans with humidistats are worth their weight in gold.

A humidistat, as you can probably guess by its name, will start and stop the fan based upon the set humidity parameters.

If the attic gets too humid, the fan will start, expelling the moist air until the level drops below your desired setting. If the humidity rises again, the fan will start again.

App Control

App control is a feature of the more modern attic fan.

These smart fans can provide not only control over the fan via your compatible smart device, but they can also provide you with valuable real time data about atmospheric conditions in your attic, alerting you if there is a serious issue with temperature or humidity, or even a fan failure.

Having this information on demand means you’ll know what’s happening before it’s too late.

Fire Shut Down

The best attic fans also have fire shut down features. If a fire is detected, the fan will stop automatically, preventing the drawing in of fresh air to fuel the blaze.

Maximum CFM

CFM stands for cubic feet per minute, and it is a measure of how much air the fan is physically capable of moving.

You might think the more CFM the better, but the reality is more nuanced – you see, it’s possible to get an attic fan that’s too powerful for your attic!

If your attic is too small for the fan, the fan will start to draw air from the rooms elsewhere in the house (the rooms you already pay to keep air conditioned) and will expel that air outside.

Not what you had in mind!

What Size Attic Fan Do I Need?

Fortunately, it’s easy to properly size your attic fan.

The rule of thumb in the industry is that, at a minimum, you need 700 CFM for every 1,000 square feet of attic space.

To apply this to your attic, simply determine the approximate square footage of your attic and multiply by 0.7.

For example, a 1,500 square foot attic would be well suited for a 1,050 CFM attic fan (1,500*0.7 = 1,050).

If you have a particularly steep or dark roof, there’s an additional adjustment you can make.

Take the above number and multiply by 1.2 if you have a steep roof, or by 1.15 for an especially dark roof.

Sticking with our 1,500 square foot example, you’d adjust the CFM to 1,260 for a steep roof (1,050 * 1.2 = 1,260) and a little over 1,200 for a dark roof (1,050 *1.15 = 1,207).

proHVACinfo | DYK Attic Fans

Our Reviews of the Best Attic Fans

Final Thoughts On The Best Attic Fans

We hope we’ve been able to provide you with some good insight on the importance of a good attic fan.

Many homeowners rush to buy box fans or pedestal fans when their air conditioning can’t seem to keep up with the summer temperatures, but those are merely band aids, and often just move hot air around the room, rather than cooling it.

By installing an attic can you can significantly reduce in your home, and give your air conditioning a fighting chance without using excess energy.

Stephen Marks

Stephen Marks

Stephen is an HVAC and home-repair enthusiast. He's here to answer any of your questions about HVAC!

Leave a Comment

Stephen Marks

Stephen Marks

Stephen is an HVAC and home-repair enthusiast. He's here to answer any of your questions about HVAC!

About proHVACinfo

You’ve got HVAC questions. We have the best answers from a network of seasoned pros.

Recently Published Guides